为什么oracle游标没有值？？？？？

Question

以下是我的脚本，在cmd下运行后，输出是0，可是我的表mmm里是有数据的
declare cursor cur
is
select id from mmm;
begin
open cur;
dbms_output.put_line(cur%ROWCOUNT);
end;
/

Answer 1

--because you do not fetch data !
declare 
cursor cur is select * from emp;
rs emp%rowtype;
begin
    open cur;
    loop
      fetch cur into rs ;
      exit when cur%notfound ;
      dbms_output.put_line(cur%ROWCOUNT);
    end loop;
    close cur;
end;
/32  PL/SQL block, executed in 0.234 sec.
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    Total execution time 0.266 sec.